This is a typically good episode in this fine Granada series from 1967. The series is in black and white, and the quality of the DVD release is only fairly good, no doubt due to the state of the source tapes. The strong suit of this episode, and the entire series, is the high quality of the acting by all concerned. William Mervyn as the lead brims with intelligence and panache, plus he has about the richest, most upper-class, English gentleman accent imaginable. Gillian Lewis and Donald Webster, as Mervyn's two assistants, give superb support. Gillian Lewis endows her character with a very pleasing charm, and Donald Webster gets to have fun in this one, too.
The budget was probably rather modest--we get no exteriors, even as establishing shots, but we do get a variety of sets: Mervyn's house, a lord's mansion, a pub. This is a show to watch to appreciate first-class British acting, by all the players, especially the three leads.